Source for file CanonicalCourse.class.php

<?php
 
require_once(OKI2."/osid/coursemanagement/CanonicalCourse.php");
require_once(HARMONI."oki2/coursemanagement/CanonicalCourseIterator.class.php");
require_once(HARMONI."oki2/shared/HarmoniStringIterator.class.php");
 
 
/**
 * CanonicalCourse contains general information about a course.     This is in
 * contrast to the CourseOffering which contains information about a concrete
 * offering of this course in a specific term and with identified people and
 * roles.  The CourseSection is the third and most specific course-related
 * object.    The section includes information about the location of the class
 * as well as the roster of students.  CanonicalCourses can contain other
 * CanonicalCourses and may be organized hierarchically, in schools,
 * departments, for majors, and so on.    For each CanonicalCourse, there are
 * zero or more offerings and for each offering, zero or more sections.     All
 * three levels have separate data for Title, Number, Description, and Id.
 * This information can be the same or different as implementations choose and
 * applications require.
 * 
 * <p>
 * OSID Version: 2.0
 * </p>
 *
 * @package harmoni.osid_v2.coursemanagement
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: CanonicalCourse.class.php,v 1.29 2007/09/04 20:25:39 adamfranco Exp $
 */
class HarmoniCanonicalCourse
    extends CanonicalCourse
{
    
    
    /**
     * @variable object $_node the node in the hierarchy.
     * @access private
     * @variable object $_id the unique id for the canonical course.
     * @access private
     * @variable object $_table the canonical course table.
     * @access private
     * @variable object Id $_canonicalCoursesId the hierarchy
     * @access private
     ***/
    var $_node;
    var $_id;
    var $_table;
    var $_hierarchy;
    
    
    
    
    /**
     * The constructor.
     * 
     * @param object Id $id 
     * @param object Node $node 
     * 
     * @access public
     * @return void 
     */
    function HarmoniCanonicalCourse($id, $node)
    {
        $this->_id =$id;
        $this->_node =$node;
        $this->_table = 'cm_can';
        $cm = Services::getService("CourseManagement");
        $this->_hierarchy =$cm->_hierarchy;
        
    }
    
 
    /**
     * Get the title for this CanonicalCourse.
     *    
     * @return string 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getTitle () { 
    
        
            return $this->_getField('title');
    }
 
    /**
     * Update the title for this CanonicalCourse.
     * 
     * @param string $title 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}
     * 
     * @access public
     */
    function updateTitle ( $title ) { 
 
        $this->_setField('title',$title);
        
    }
 
    /**
     * Get the number for this CanonicalCourse.
     *    
     * @return string 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getNumber () {
        
        
        
        
        return $this->_getField('number');
    }
 
    /**
     * Update the number for this CanonicalCourse.
     * 
     * @param string $number 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}
     * 
     * @access public
     */
    function updateNumber ( $number ) { 
    
        
    $this->_setField('number',$number);
    
        
        
    }
 
    /**
     * Get the description for this CanonicalCourse.  Returns null if no description exists
     *    
     * @return string 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getDescription () { 
        return $this->_node->getDescription();
    }
 
    /**
     * Update the description for this CanonicalCourse.
     * 
     * @param string $description 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}
     * 
     * @access public
     */
    function updateDescription ( $description ) { 
        $this->_node->updateDescription($description);
    }
    
    /**
     * Get the display name for this CanonicalCourse.
     *    
     * @return string 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getDisplayName () {  
        return $this->_node->getDisplayName();
    } 
    
    /**
     * Update the display name for this CanonicalCourse.
     * 
     * @param string $displayName 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}
     * 
     * @access public
     */
    function updateDisplayName ( $displayName ) { 
        $this->_node->updateDisplayName($displayName);
    } 
 
    /**
     * Get the unique Id for this CanonicalCourse.
     *    
     * @return object Id 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
     
     
    function getId () { 
        return $this->_id;
    }
 
    /**
     * Get the Course Type for this CanonicalCourse.  This Type is meaningful
     * to the implementation and applications and are not specified by the
     * OSID.
     *    
     * @return object Type 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getCourseType () { 
        return $this->_getType('can');
    }
 
    /**
     * Create a new CanonicalCourse.  The display name defaults to the title, but this can be changed later.
     * 
     * @param string $title 
     * @param string $number 
     * @param string $description 
     * @param object Type $courseType 
     * @param object Type $courseStatusType 
     * @param float $credits 
     *    
     * @return object CanonicalCourse 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNKNOWN_TYPE
     *            UNKNOWN_TYPE}
     * 
     * @access public
     */
    function createCanonicalCourse ( $title, $number, $description, $courseType, $courseStatusType, $credits ) { 
    
        
        $idManager = Services::getService("IdManager");
        $id=$idManager->createId();
 
 
        $type = new Type("CourseManagement","edu.middlebury", "CanonicalCourse");
        $node=$this->_hierarchy->createNode($id,$this->_id,$type,$title,$description);
 
        $dbManager= Services::getService("DatabaseManager");
        $query= new InsertQuery;
 
        $query->setTable('cm_can');
 
        $query->setColumns(array('id','number','credits','equivalent','fk_cm_can_type','title','fk_cm_can_stat_type'));
 
        $values[]="'".addslashes($id->getIdString())."'";
        $values[]="'".addslashes($number)."'";
        $values[]="'".addslashes($credits)."'";
        $values[]="'".addslashes($id->getIdString())."'";
        $values[]="'".$this->_typeToIndex('can',$courseType)."'";
        $values[]="'".addslashes($title)."'";
        $values[]="'".$this->_typeToIndex('can_stat',$courseStatusType)."'";
        $query->addRowOfValues($values);
 
 
 
        $dbManager->query($query);
 
        $ret = new HarmoniCanonicalCourse($id, $node);
        return $ret;
    }
 
    /**
     * Get all CanonicalCourses.
     *    
     * @return object CanonicalCourseIterator 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getCanonicalCourses () { 
        $cm = Services::getService("CourseManagement");
        
        //get the children
        $node =$this->_node;
        $nodeType =$node->getType();
        $children =$node->getChildren();
        
        //iterate throught the children
        $array = array();
        while($children->hasNextNode()){
            $child =$children->nextNode();
            $currNodeType =$child->getType();
            
            //If this node is also a CanonicalCourse
            if($currNodeType->isEqual($nodeType)){
                $id =$child->getId();
                $array[] =$cm->getCanonicalCourse($id);
            }        
        }
        
        //convert to an iterator and return
        $ret = new HarmoniCanonicalCourseIterator($array);
        return $ret;
        
    }
 
    /**
     * Get all CanonicalCourses of the specified Type.
     * 
     * @param object Type $courseType 
     *    
     * @return object CanonicalCourseIterator 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNKNOWN_TYPE
     *            UNKNOWN_TYPE}
     * 
     * @access public
     */
    function getCanonicalCoursesByType ( $courseType ) { 
        $cm = Services::getService("CourseManagement");
        
        //get the children
        $node =$this->_node;
        $nodeType =$node->getType();
        $children =$node->getChildren();
        
        //iterate throught the children
        $array = array();
        while($children->hasNextNode()){
            $child =$children->nextNode();
            $currNodeType =$child->getType();
            
            //If this node is also a CanonicalCourse
            if($currNodeType->isEqual($nodeType)){
                $id =$child->getId();
                $course =$cm->getCanonicalCourse($id);
                if($courseType->isEqual($course->getCourseType())){
                    $array[] =$cm->getCanonicalCourse($id);                
                }    
            }        
        }
        
        //convert to an iterator and return
        $ret = new HarmoniCanonicalCourseIterator($array);
        return $ret;
    } 
 
    /**
     * Create a new CourseOffering.  The default display name is the title of the course.
     *
     * The display name defaults to the title.  If the title,
     * number or displayName are left null, they default to the values of the creating agent.
     * Niether of these defaults are in the OSID, however.
     * 
     * @param string $title 
     * @param string $number 
     * @param string $description 
     * @param object Id $termId 
     * @param object Type $offeringType 
     * @param object Type $offeringStatusType 
     * @param object Type $courseGradeType 
     *    
     * @return object CourseOffering 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNKNOWN_TYPE
     *            UNKNOWN_TYPE}
     * 
     * @access public
     */
    function createCourseOffering ( $title, $number, $description, $termId, $offeringType, $offeringStatusType, $courseGradeType ) { 
        
        //set any defaults
        if(is_null($title)){
            $title = $this->getTitle();
        }
        if(is_null($number)){
            $number = $this->getNumber();
        }
        if(is_null($description)){
            $description = $this->getDescription();
        }
        
        
        $idManager = Services::getService("IdManager");
        $id=$idManager->createId();
 
        
        
        
        
 
        $type = new Type("CourseManagement","edu.middlebury", "CourseOffering");
        $node=$this->_hierarchy->createNode($id,$this->_id,$type,$title,$description);
        
        
        
        
 
        $dbManager= Services::getService("DatabaseManager");
        $query= new InsertQuery;
 
        $query->setTable('cm_offer');
 
        $query->setColumns(array('id','fk_gr_grade_type','fk_cm_term',
                                'fk_cm_offer_stat_type','fk_cm_offer_type','title','number'));
        
        $values[]="'".addslashes($id->getIdString())."'";
        $gm = Services::getService('Grading');
        $typeIndex = $gm->_typeToIndex('grade',$courseGradeType);
        $values[]="'".addslashes($typeIndex)."'";
        $values[]="'".addslashes($termId->getIdString())."'";
        $values[]="'".addslashes($this->_typeToIndex('offer_stat',$offeringStatusType))."'";
        $values[]="'".addslashes($this->_typeToIndex('offer',$offeringType))."'";
        $values[]="'".addslashes($title)."'";
        $values[]="'".addslashes($number)."'";
        
        $query->addRowOfValues($values);
 
        $dbManager->query($query);
 
        $ret = new HarmoniCourseOffering($id, $node);
        return $ret;
 
        
    } 
    
    /**
     * Delete a CourseOffering.
     * 
     * @param object Id $courseOfferingId 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNKNOWN_ID
     *            UNKNOWN_ID}
     * 
     * @access public
     */
    function deleteCourseOffering ( $courseOfferingId ) { 
      
      $node =$this->_hierarchy->getNode($courseOfferingId);
 
    $iterator =$node->getChildren();
    
    if($iterator->hasNextNode()){
      print "<b>Warning!</b> Can't delete CourseOfferings without deleting their CourseSections";
      return;
    }
      
      
        $this->_hierarchy->deleteNode($courseOfferingId);
 
 
 
        $dbManager = Services::getService("DatabaseManager");
        $query= new DeleteQuery;
 
 
        $query->setTable('cm_offer');
 
        $query->addWhere("id=".addslashes($courseOfferingId->getIdString()));
        $dbManager->query($query);
    } 
 
    /**
     * Get all CourseOfferings that belong to this CanonicalCourse.
     *    
     * @return object CourseOfferingIterator 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getCourseOfferings () { 
        
 
        
        $nodeIterator =$this->_node->getChildren();
        
        $array = array();
        $idManager=  Services::getService("IdManager");
        $cm=  Services::getService("CourseManagement");
        while($nodeIterator->hasNextNode()){
            $childNode =$nodeIterator->nextNode();
            $nodeType =$childNode->getType();
            if($nodeType->getKeyWord()!="CourseOffering"){
                continue;    
            }    
            $id =$childNode->getId();
            $courseOffering =$cm->getCourseOffering($id);            
            $array[] =$courseOffering;
        }
        $ret = new  HarmoniCourseOfferingIterator($array);
        return $ret;
    } 
 
    /**
     * Get all CourseOfferings of the specified Type that belong to this CanonicalCourse.
     * 
     * @param object Type $offeringType 
     *    
     * @return object CourseOfferingIterator 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNKNOWN_TYPE
     *            UNKNOWN_TYPE}
     * 
     * @access public
     */
    function getCourseOfferingsByType ( $offeringType ) { 
    
        $nodeIterator =$this->_node->getChildren();
        
        $array = array();
        $idManager=  Services::getService("IdManager");
        $cm=  Services::getService("CourseManagement");
        $typeIndex=$cm->_typeToIndex('offer',$offeringType);
        
        while($nodeIterator->hasNextNode()){
            $childNode =$nodeIterator->nextNode();
            $nodeType =$childNode->getType();
            if($nodeType->getKeyWord()!="CourseOffering"){
                continue;    
            }    
            $courseOffering =$cm->getCourseOffering($childNode->getId());
            if($typeIndex == $courseOffering->_getField('fk_cm_offer_type')){
                $array[] =$courseOffering;
            }
        }
        $ret = new  HarmoniCourseOfferingIterator($array);
        return $ret;
 
    } 
 
    /**
     * Add an equivalent course which are for mapping courses across
     * departments, schools, or institutions as well as for providing new
     * courses that map to previous ones.  This can be used for
     * cross-listening.     Note that if course A is equivalent to course B it
     * does not necessarily follow that course B is equivalent to course A.
     * Course A could cover a superset of the mateiral in course B.
     * 
     * @param object Id $canonicalCourseId 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#ALREADY_ADDED
     *            ALREADY_ADDED}
     * 
     * @access public
     */
    function addEquivalentCourse ( $canonicalCourseId ) {
        //Courses are equivalent if they have the same id in the equivalent field
        //The id chosen is the lowest of the ids
        //getField()
        
 
        $cm = Services::getService("CourseManagement");
        
        $course =$cm->getCanonicalCourse($canonicalCourseId);
        $courseEquivalent = $course->_getField('equivalent');
        $thisEquivalent = $this->_getField('equivalent');
        $comp = strcasecmp($courseEquivalent,$thisEquivalent);
        if($comp==0){
            return;    
        } elseif ($comp > 0){
            $min = $thisEquivalent;
            $courseIterator =$course->getEquivalentCourses();
            $course->_setField('equivalent',$min);
        }else{
            $min = $courseEquivalent;
            $courseIterator =$this->getEquivalentCourses();
            $this->_setField('equivalent',$min);
            
        }
        while($courseIterator->hasNextCanonicalCourse()){
            $course = $courseIterator->nextCanonicalCourse();
            $course->_setField('equivalent', $min);
        }
    
    } 
 
    /**
     * Assures that the course passed in as a parameter is no longer
     * equivalent to any other courses.  It does not matter which course
     * calls the function.  In fact, it may make the most sense for courses to
     * call the function on themselves.
     * 
     * @param object Id $canonicalCourseId 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNKNOWN_ID
     *            UNKNOWN_ID}
     * 
     * @access public
     */
    function removeEquivalentCourse ( $canonicalCourseId ) {         
        $cm = Services::getService("CourseManagement");        
        $course =$cm->getCanonicalCourse($canonicalCourseId);        
        $courseIterator =$course->getEquivalentCourses();    
 
            
        if(!$courseIterator->hasNextCanonicalCourse()){
            return;    
        }
        
        
        $courseEquivalent = $course->_getField('equivalent');
        $idString=$canonicalCourseId->getIdString();
        
        
                
        if($courseEquivalent!=$idString){
            $course->_setField('equivalent',$idString);
            return;
        }
        
        //Hahahahaa!  I crack myself up.
        $first =true;
        while($courseIterator->hasNextCanonicalCourse()){
            $currCourse =$courseIterator->nextCanonicalCourse();
            $currId =$currCourse->getId();
            
            
            
            
            $currIdString = $currId->getIdString();        
            
            if($first || strcasecmp($currIdString,$minSoFar) < 0){
                $minSoFar = $currIdString;        
                $first=false;        
            }    
        }
        
        
        
        $courseIterator =$course->getEquivalentCourses();
        
        while($courseIterator->hasNextCanonicalCourse()){
            
            
            $course =$courseIterator->nextCanonicalCourse();
            $course->_setField('equivalent',$minSoFar);        
        }
        
        
    } 
 
    /**
     * Get all equivalent courses for this CanonicalCourse.
     *    
     * @return object CanonicalCourseIterator 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getEquivalentCourses () { 
        
        $dbManager = Services::getService("DatabaseManager");
        $cm = Services::getService("CourseManagement");
        $query= new SelectQuery;
        $query->addTable($this->_table);
        $query->addColumn('id');
        $query->addWhere("equivalent ='".$this->_getField('equivalent')."'");
        $res=$dbManager->query($query);
        $array=array();
        $idManager= Services::getService('IdManager');
        $myIdString = $this->_id->getIdString();
        while($res->hasMoreRows()){
            $row = $res->getCurrentRow();
            $res->advanceRow();
            if($row['id']==$myIdString){
                continue;
            }
            $array[] = $cm->getCanonicalCourse($idManager->getId($row['id']));
        }
        $ret = new HarmoniCanonicalCourseIterator($array);
        return $ret;
    } 
 
    /**
     * Add a Topic for this CanonicalCourse.
     * 
     * @param string $topic 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#ALREADY_ADDED
     *            ALREADY_ADDED}
     * 
     * @access public
     */
    function addTopic ( $topic ) { 
        $dbManager = Services::getService("DatabaseManager");
        $query= new SelectQuery;
        $query->addTable('cm_topics');
        $query->addWhere("fk_cm_can='".$this->_id->getIdString()."'");
        $query->addWhere("topic='".addslashes($topic)."'");
        //not really needed, but it keeps this from crashing.
        $query->addColumn('topic');
        $res=$dbManager->query($query);
 
 
 
        if($res->getNumberOfRows()==0){
            $query= new InsertQuery;
            $query->setTable('cm_topics');
            $values[]="'".addslashes($this->_id->getIdString())."'";
            $values[]="'".addslashes($topic)."'";    
            $query->setColumns(array('fk_cm_can','topic'));    
                    
            $query->addRowOfValues($values);            
            $result =$dbManager->query($query);
        }elseif($res->getNumberOfRows()==1){
            //do nothing
        }else{
            print "\n<b>Warning!<\b> The Topic with course ".$this->getDisplayName()." and description ".$topic." is not unique--there are ".$res->getNumberOfRows()." copies.\n";
 
        }
    } 
 
    /**
     * Remove a Topic for this CanonicalCourse.
     * 
     * @param string $topic 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}
     * 
     * @access public
     */
    function removeTopic ( $topic ) { 
        $dbManager = Services::getService("DatabaseManager");
        $query= new DeleteQuery;
        $query->setTable('cm_topics');
        $query->addWhere("fk_cm_can='".$this->_id->getIdString()."'");
        $query->addWhere("topic='".addslashes($topic)."'");
        $dbManager->query($query);
 
    } 
 
    /**
     * Get all Topics for this CanonicalCourse.
     *    
     * @return object StringIterator 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getTopics () { 
        
        
        
        
        
        $dbManager = Services::getService("DatabaseManager");
        $query= new SelectQuery;
        $query->addTable('cm_topics');
        $query->addWhere("fk_cm_can='".$this->_id->getIdString()."'");
        $query->addColumn('topic');
        $res=$dbManager->query($query);
        $array=array();
        while($res->hasMoreRows()){
            $row = $res->getCurrentRow();
            $res->advanceRow();
            $array[]=$row['topic'];
        }
        $ret = new HarmoniStringIterator($array);
        return $ret;
    } 
 
    /**
     * Get the credits for this CanonicalCourse.
     *    
     * @return float 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getCredits () { 
        
        return $this->_getField('credits');
    } 
 
    /**
     * Update the credits for this CanonicalCourse.
     * 
     * @param float $credits 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}
     * 
     * @access public
     */
    function updateCredits ( $credits ) { 
        $this->_setField('credits',$credits);
    
    } 
 
    /**
     * Get the Status for this CanonicalCourse.
     *    
     * @return object Type 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getStatus () { 
        return $this->_getType('can_stat');
        
    
    } 
 
    /**
     * Update the Status for this CanonicalCourse.
     * 
     * @param object Type $statusType 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
     *            NULL_ARGUMENT}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNKNOWN_TYPE
     *            UNKNOWN_TYPE}
     * 
     * @access public
     */
    function updateStatus ( $statusType ) { 
 
        $index = $this->_typeToIndex('can_stat',$statusType);
        $this->_setField('fk_cm_can_stat_type',$index);
    } 
    
    /**
     * Get all the Property Types for  CanonicalCourse.  There is is only
     * One type of property associated with each course object.
     *    
     * @return object TypeIterator 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getPropertyTypes () { 
        $courseType =$this->getCourseType();
        $propertiesType = new Type("PropertiesType", $courseType->getAuthority(), "properties");
        $array = array($propertiesType);
        $typeIterator = new HarmoniTypeIterator($array);
        return $typeIterator;
    } 
 
    /**
     * Get the Properties associated with this CanonicalCourse.  There is is only
     * One type of property associated with each course object.
     *    
     * @return object PropertiesIterator 
     * 
     * @throws object CourseManagementException An exception
     *            with one of the following messages defined in
     *            org.osid.coursemanagement.CourseManagementException may be
     *            thrown:    {@link }
     *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
     *            OPERATION_FAILED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
     *            PERMISSION_DENIED}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
     *            CONFIGURATION_ERROR}, {@link }
     *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
     *            UNIMPLEMENTED}
     * 
     * @access public
     */
    function getProperties () { 
        $array = array($this->_getProperties());
        $ret = new HarmoniPropertiesIterator($array);        
        return $ret;//return the iterator
        
    } 
    
    
    
    /**
    * Get the Properties of this Type associated with this CanonicalCourse.  There is is only
    * One type of property associated with each course object.
    *
    * @param object Type $propertiesType 
    *
    * @return object Properties 
    *
    * @throws object CourseManagementException An exception
    *            with one of the following messages defined in
    *            org.osid.coursemanagement.CourseManagementException may be
    *            thrown:    {@link }
    *            org.osid.coursemanagement.CourseManagementException#OPERATION_FAILED
    *            OPERATION_FAILED}, {@link }
    *            org.osid.coursemanagement.CourseManagementException#PERMISSION_DENIED
    *            PERMISSION_DENIED}, {@link }
    *            org.osid.coursemanagement.CourseManagementException#CONFIGURATION_ERROR
    *            CONFIGURATION_ERROR}, {@link }
    *            org.osid.coursemanagement.CourseManagementException#UNIMPLEMENTED
    *            UNIMPLEMENTED}, {@link }
    *            org.osid.coursemanagement.CourseManagementException#NULL_ARGUMENT
    *            NULL_ARGUMENT}, {@link }
    *            org.osid.coursemanagement.CourseManagementException#UNKNOWN_TYPE
    *            UNKNOWN_TYPE}
    *
    * @access public
    */
    function getPropertiesByType ( $propertiesType ) {
        $courseType =$this->getCourseType();
        $propType = new Type("PropertiesType", $courseType->getAuthority(), "properties");         
        if($propertiesType->isEqualTo($propType)){
            return $this->_getProperties();
        }
        return null;
        
        
        
    }
    
    
    /**
    * Get a Properties object with the information about this object.
    *
    * @return object Properties 
    *
    * @access private
    */
    function _getProperties(){
        $dbManager = Services::getService("DatabaseManager");
        
        //get the record
        $query = new SelectQuery();
        $query->addTable('cm_can');
        $query->addColumn("*");
        $query->addWhere("id='".addslashes($this->_id->getIdString())."'");                
        $res=$dbManager->query($query);
        
        
        
        //make sure we can find that course
        if(!$res->hasMoreRows()){
            print "<b>Warning!</b>  Can't get Properties of Course with id ".$this->_id." since that id wasn't found in the database.";
            return null;    
        }
        $row = $res->getCurrentRow();//grab (hopefully) the only row        
        
        //make a type
        $courseType =$this->getCourseType();    
        $propertiesType = new Type("PropertiesType", $courseType->getAuthority(), "properties"); 
                
        //create a custom Properties object
        $idManager = Services::getService("Id");
        $property = new HarmoniProperties($propertiesType);
        $property->addProperty('display_name', $this->_node->getDisplayName());
        $property->addProperty('title', $row['title']);
        $property->addProperty('description', $this->_node->getDescription());    
        $property->addProperty('id', $idManager->getId($row['id']));
        $property->addProperty('number', $row['number']);
        $property->addProperty('credits', $row['credits']);
        $property->addProperty('equivalent_id', $idManager->getId($row['equivalent']));
        $property->addProperty('type', $courseType);
 
        $statusType =$this->getStatus();
        $property->addProperty('status_type', $statusType);
 
        
        $res->free();    
        return $property;
        
        
    }
    
    
    
    
    
    function _typeToIndex($typename, $type)
    {    
        $cm=Services::getService("CourseManagement");
        return $cm->_typeToIndex($typename, $type);
    }
    
    function _getTypes($typename)
    {    
        $cm=Services::getService("CourseManagement");
        return $cm->_getTypes($typename);
    }
    
    function _getField($key)
    {
        $cm=Services::getService("CourseManagement");
        return $cm->_getField($this->_id,$this->_table,$key);
    }
    
    
    function _getType($typename){
        $cm=Services::getService("CourseManagement");
        return $cm->_getType($this->_id,$this->_table,$typename);
    }
    
    function _setField($key, $value)
    {
        $cm=Services::getService("CourseManagement");
        return $cm->_setField($this->_id,$this->_table,$key, $value);        
    }
    
    
    
    
    
    
}
 
?>